Boat dive safety line

[chuckprice]

Newbie here, forgive me if this topic is misplaced.

I recently certified in Monterey. I did my first boat dive on Memorial Day with the Monterey Express. Great dive onto Ball Buster Reef with a couple of expert buddies (Thanks guys).

I just got back from a trip to NC, and did a wreck dive through Discovery Diving in Beaufort. That dive is probably a topic for another place on the board, but I'll be happy to share if anyone is interested (it was wonderful).

What I liked about the particular dive *boat* is that they had a safety line at approx. 15 feet, running from the stern of the boat to the anchor. They also hung air off the stern in case someone miscalculated on the way back up and needed extra for the safety stop.

The safety line made it easy to 1) find the anchor line, 2) do the safety stop on the return, and 3) find the spare air (which no one needed on our trip).

I don't recall that Monterey Express had such a line on their boat. It seems like such a simple addition and safety service, I wonder why not? Do other boats in Monterey employ a safety line? If not, why not?

I look forward to diving with some of you folks as I progress in this sport!

 

[DA Aquamaster]

The line from the stern to the anchor line (and sometimes also a decent/ascent line) is called a current line (or granny line)and makes it easier for the divers to move from the stern up current to the anchor line or decent/ascent line. The current line is normally shackled to the anchor line at about 20'.

If a very long anchor line is required a separate decent/ascent line will be used and will be attached where the anchor line meets the current line about 20 ft under the surface. This line then leads more or less straight to the bottom.

A safety line is a line run off the stern to the safety tank at 15-20 ft.

A trail line is a line run off the stern to a float trailing behind the boat to accomodate divers who have just entered or are waiting to exit the water.

The current line, descent/ascent line and trail line can be very important with a moored or anchored dive boat in a current but are a lot less important and may not be selected for use in conditions where there is little or no current or where the dive is conducted as a live boat dive or drift dive.

 

[Uncle Pug]

This thread has a new home in the boat diving forum.

We call the line you mention a *granny line* and I put one out whenever we anchor and there is current. I will also put out a tagline behind the boat with a ball float at the end.

But we never hang tanks. If you need the gas then you need to carry the gas with you. We can't guarantee that we will make it back to the anchor line (though that is nice) and so we take what we need with us.

However.... there was a time back in the old days before DIR darkened my door that we did hang tanks... and I can remember needing it after a second dive, low on air(!) with a small deco situation.

Of course this was also the time that my hands were tied together with fishing line from the lures I'd been picking up, the current was running away from the boat, my same~ocean~buddy was somewhere in the same ocean and of course I had no idea where the anchor line was. I ascended to 10; and sucked a vacuum on my tank to get in as much of a stop as I could while drifting further from home. The hang tank was hanging happily a quarter mile away when I surfaced.

 

[Chuck Tribolet]

In Monterey, the term "current line" is used for a floating
line 100' or more long that is trailed behind the boat.
The only time I've ever seen what Uncle Pug called a
granny line was at the Farallones, to allow the divers to
get from the swim platform to the anchor line without
being on the surface (Landlord avoidance).

Hang tank? The Monterey boats don't generally do hang
tanks. You are a certified diver. You aren't supposed to
run out of air.

 

[chuckprice]

Thanks for the info guys! Now I will speak more intelligently when I climb onto a boat.

Uncle Pug, is your reluctance to hang tanks related to legal liability as a commercial operator? Otherwise, it seems that one could never be too safe, and extra gas doesn't seems only to be a help, not a hinderance. Your argument against uses an example where you came up too far away to make use of the air. Sure, in that case it didn't help, but perhaps in some other case it would have helped. (I'm not judging, just asking as a newbie.)

I certainly agree that one should never count on that air, and that one should bring the gas they need.

Our dive captain in NC said that the air was there, but not to plan on using it.

If you just want to discourage folks from depending on it, maybe a dive boat operator could work out a scheme for charging for use! Say, a dollar per breath...

 

[Dragracer]

The Sea Fox out of Dunedin, FL. has a trapeeze (sp) at 15' for a saftey stop. A line is run from the trapeeze to the anchor line by the Divemaster to make the decents/ascents easy. They hang a regulator from a tank on the boat for emergency air, and it's even with the trapeeze. While I agree, you shouldn't need it if you monitor your air, I like having it available.

 

[miketsp]

Signature:
You need only two tools: WD-40 and Duct Tape. If it doesn't move and it should, use WD-40. If it moves and shouldn't, use the duct tape.

.

Off subject - Your signature reminds me of military days.
You just need to add:

If it moves and should - salute it. If it doesn't move and shouldn't - paint it!

 

[RICHinNC]

Chuck...one thing you need to watch for on the NC boats is the hang bar a number of them use. It is basically a piece of pipe suspended at 15ft so you can "hang" and do your decomp.

The thing you need to be aware of is in NC the waters are seldom flat. And that boat is going to be going up and down....a lot. If you hang on to that bar with a death grip and go up with it....you could get seriously injured a couple of ways. One being the boat will sink faster than you and the bar on the down drop....and whack goes the head. Ive seen that happen on every NC dive I have made. Try doing your decomp at 20 ft instead.

 

[DA Aquamaster]

Thanks for the info guys! Now I will speak more intelligently when I climb onto a boat.

Uncle Pug, is your reluctance to hang tanks related to legal liability as a commercial operator? Otherwise, it seems that one could never be too safe, and extra gas doesn't seems only to be a help, not a hinderance. Your argument against uses an example where you came up too far away to make use of the air. Sure, in that case it didn't help, but perhaps in some other case it would have helped. (I'm not judging, just asking as a newbie.)

I certainly agree that one should never count on that air, and that one should bring the gas they need.

Our dive captain in NC said that the air was there, but not to plan on using it.

I'm not sure about Uncle Pug's reasons but I will normally not bother with the saftey tank when diving with experienced divers as there is really no need if the diver is properly configured and equipped and is using proper gas planning with a 1/3 reserve. Stuff can still happen but there should still be a buddy in the water with adequate gas in reserve to address the situation.

When doing deep dives with realtively newly minted deep divers or divers with whom I am not very familiar, I will put a saftey tank with Nitrox 50 at 20 ft as the potential for a diver to blow their plan or run short of gas is more likely and the saftey tank just seems prudent to me.

 

[SDAnderson]

The safety line that chuckprice is talking about is a submerged line, weighted down so that it stays at a constant depth of about 15 feet. It's part of what I've come to know as a Carolina Rig and I think it's a great idea. An adaptation suited to the strong currents and heavy seas of the Outer Banks, it serves both as a granny line (the surface line running from the stern to the bow mooring line on many boats) and a deco bar (the horizontal bar hung at 20' as an assist on some boats).

I wish all boats would use it, but the Carolina Rig takes a few minutes longer to deploy and retrieve and...